The invention is based on a fuel injection pump having an adjusting device as generally defined.
In a known adjusting device of this kind (German Offenlegungsschrift No. 29 08 235), a full-load stop for a quantity adjusting device of a fuel injection pump is set by a stepping motor and the quantity adjusting device is actuated by a centrifugal governor, in cooperating with a load lever as already set forth in existing conventional fuel injection pumps. The stepping motor acts directly upon the stop and must be adjusted as needed counter to the force of the regulating spring. To this end, substantial adjusting forces must be exerted, which is disadvantageous, and furthermore the danger exists that the stepping motor may not be able to execute each of its adjusting increments. Especially if the position of the stop is to be determined in accordance with a control value, it is important for such a stepping motor to be assured of executing all its increments, or else, as provided in the known device, a feedback element for the position of the stop is required. This necessitates substantial additional expense, however, in order to attain the advantage offered by the stepping motor and its mode of operation; that is, the terminal position of a stop adjusted thereby is the product of the number of adjusting increments. The advantage of using a stepping motor, i.e., that feedback is not necessary for precise adjusting processes, would be lost after all because feedback is becoming necessary in the state of the art.